Characterization of Five Fungal Endophytes Producing Cajaninstilbene Acid Isolated from Pigeon Pea [Cajanus cajan (L.) Millsp.]

Five fungal endophytes (K4, K5, K6, K9, K14) producing Cajaninstilbene acid (CSA, 3-hydroxy-4-prenyl-5-methoxystilbene-2-carboxylic acid) were isolated from the roots of pigeon pea [Cajanus cajan (L.) Millsp.]. CSA is responsible for the prominent pharmacological activities in pigeon pea. The amount of CSA in culture solution varied among the five fungal endophytes. K4 produced the highest levels of CSA (1037.13 µg/L) among the endophytes tested after incubation for five days. Both morphological characteristics and molecular methods were used for species identification of fungal endophytes. The five endophytic isolates were characterized by analyzing the internal transcribed spacer (ITS) rRNA and β-tubulin genes. The K4, K5, K9 and K14 strains isolated from pigeon pea roots were found to be closely related to the species Fusarium oxysporum. K6 was identified as Neonectria macrodidym. The present study is the first report on the isolation and identification of fungal endophytes producing CSA in pigeon pea. The study also provides a scientific base for large scale production of CSA

The Intra-Host Evolution of SARS-CoV-2 After Neutralizing Antibody Therapy, Revealed by Nanopore Sequencing

In the context of two Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) outbreaks involving local transmission and an international flight, we used meta-transcriptome and multi-amplicon sequencing to successfully acquire the complete viral genome sequences from clinical samples with varying viral loads. To enhance viral transcript presence, we used a primer pool for reverse transcription and sequenced the samples with nanopore sequencing, and successfully acquired the entire genomic sequence of the virus within less than 4 hours. In a substantial sample size of approximately 800 clinical specimens, we thoroughly examined and compared different sequencing methods. Meta-transcriptome sequencing was effective for samples with viral reverse transcription polymerase chain reaction (RT-PCR) threshold cycle (Ct) values below 22, whereas multi-amplicon sequencing was effective across a wide Ct range. Additionally, enriched nanopore sequencing was valuable in capturing the complete genome sequence when rapid results are required. Through monitoring the viral quasi-species in individual patients, we observed ongoing viral evolution during neutralizing antibody therapy and found evidence that vaccine administration may affect the development of viral quasi-species. Overall, our findings highlight the potential of this viral sequencing strategy for both outbreak control and patient treatment